The present invention relates to bone removal and vascular visualization in medical image data, and more particularly, to removal of bone voxels from 3D computed tomography angiography images in order to visualize vessels in the 3D computed tomography angiography images.
Computed Tomography Angiography (CTA) is a medical imaging technique that is often used to visualize the blood vessels in a patient's body. Computed tomography (CT) combines a series of X-ray images taken from different angles and uses computer processing to create cross-sectional images, or slices, of bones, blood vessels and soft tissues inside the body. The cross-sectional images, or slices, can be combined to generate 3D CT volumes. In CTA, a contrast agent is injected into the bloodstream of the patient prior to CT imaging in order to generate contrast enhanced CT images that visualize the patient's vessels.
In CTA images, there is an overlapping intensity between distribution bones and contrast enhanced vessels. That is bone and contrast enhance vessels appear with similar intensity in CTA images. Accordingly, bones can be a major obstacle in the visualization and analysis of vessel trees, aneurisms, and calcifications using CTA, and it is desirable to remove bone structures from CTA images in order to achieve a better visualization of the vessels. In the past, manual editing techniques have been used to extract and remove bone structures from the image data. However, the tedious and long operating time required for manual editing is prohibitive for it to be of practical use. Furthermore, due to image resolution and noise in the image data, bones and vessels with overlapping intensity distributions often appear to be connected, which creates significant challenges in automated segmentation and removal of bone structures from the image data.